I am not an expert on the technical side of how domain extensions are ranked by the search engines, and I never said that a .US domain would not rank well. That's why I used the words "most likely". But I do think that most people would agree that this is not the preferred domain extension to use. I don't think I would ever really bother with registering one, but I suppose you could give it a shot and see what happens.
I do know that there are all sorts of variables that go into good search engine placement, and the domain extension is by far not the most important aspect of it, by any means. But if you register it, good luck to you.
Hope all works well.
